bug#61684: can't compose 'with-patch' with 'with-source'

[Maxim Cournoyer]

Hi,

Given 'with-source' discards any patch from the original source, I thought
I could at least add them back via 'with-patch', but it appears this
does not work:

--8<---------------cut here---------------start------------->8---
scheme@(gnu packages jami)> (options->transformation 
                             `((with-source . 
"libjami@20230220.0=/home/maxim/src/jami/jami-20230220.0.tar.gz")
                               (with-patch . ,(string-append 
                                               "libjami=" (search-patch 
                                                           
"jami-disable-integration-tests.patch")))))
$6 = #<procedure 7f2cd01a97e0 at guix/transformations.scm:1010:2 (obj)>
scheme@(gnu packages jami)> ($6 libjami)
$7 = #<package libjami@20230220.0 guix/transformations.scm:1002 7f2ccc8386e0>
scheme@(gnu packages jami)> (package-source $7)
$8 = #<<downloaded-file> uri: "/home/maxim/src/jami/jami-20230220.0.tar.gz" 
recursive?: #t>
scheme@(gnu packages jami)>
--8<---------------cut here---------------end--------------->8---

The downloaded-file resulting package source has lost the patch, and no
error got produced, leaving the user to discover this limitation by
themselves.

-- 
Thanks,
Maxim